Head of Security Engineering: Hands-On AI Security

Harrison Clarke; San Francisco (CA); On-site; USD 250,000 - 350,000; Full time

Job summary

Harrison Clarke is partnering with a high-growth AI company to hire its first dedicated security leader. This is a true 0 to 1 security role, defining and building the function from the ground up while remaining deeply hands-on across security engineering, cloud, identity, apps, and AI-specific threats.

You’ll own strategy, architecture, threat modeling, and incident readiness, partnering with engineering and leadership.

Qualifications

• 8+ years in security engineering, product security, infra security or related fields.
• Hands-on engineering background required; not purely managerial.
• Experience as first or early security hire in a startup.
• Strong coding ability in Python, Go or similar.
• Deep expertise in at least one security domain with breadth as a generalist.
• Solid understanding of cloud infrastructure, identity, app security, and modern dev environments.
• Offensive security mindset through red teaming, pentesting, or adversarial testing.
• Genuine interest in AI security and emergent threats.
• Ability to work autonomously and solve novel problems.
• Excellent communication with engineers and leadership.

Responsibilities

• Build the security function from ground up: strategy, architecture, roadmap, tooling, implementation.
• Design and implement security across cloud, IAM, endpoints, apps, and internal systems.
• Establish security standards and controls with minimal friction for engineering teams.
• Develop threat models for AI/ML systems and infra surfaces.
• Partner with engineering on architecture reviews, threat modeling, testing, and improvements.
• Hands-on security engineering, including coding and internal tooling when appropriate.
• Manage external security/IT partners and decide what to bring in-house.
• Lay foundations for SOC 2, ISO 27001, and future compliance initiatives.
• Own incident preparedness, detection, response, and post-incident improvements.
• Help shape long-term security org and build a small, highly technical team.

Skills

Hands-on engineering

Python or Go

Cloud security

Threat modeling

Security leadership

Security architecture

Communication with leadership

Tools

Cloud tooling

Job description

Harrison Clarke is partnering with a high-growth AI company to hire its first dedicated security leader. This is a true 0 to 1 security role, defining and building the function from the ground up while remaining deeply hands-on across security engineering, cloud, identity, apps, and AI-specific threats.

You’ll own strategy, architecture, threat modeling, and incident readiness, partnering with engineering and leadership.